Surveys and questionnaires have become quite commonplace as a means to elicit judgments about nearly everything. From how we rate the aesthetic appeal of an automobile model to our favorite movies, it is increasingly common to find at our disposal a survey or questionnaire asking us our opinion of, for example, the car dealership or the popcorn at the movies. Typical questionnaires or surveys query respondents to rate or evaluate a plurality of factors at one time. It is quite common to utilize a scale, for example, below average--average--above average, to rate the relative performance of a person or organization. Another common scale is an ordinal scale, commonly referred to as a Likert scale, whereby a respondent is asked to judge on a scale of 1-5, where 1 is strongly agree and 5 is strongly disagree, with the proposition queried.
Oftentimes results of surveys or questionnaires are summarized in order to compare the responses for different items for such purposes as deriving priorities. Frequency distributions of the results are also used to graphically portray the results of the items on the survey. Measures of central tendency, such as averages, is also utilized as a means to present survey results. In this way, the average response of each survey item can be used to assign priorities to the items by the user of the survey. However, in order for an average to be mathematically meaningful, the measure must be interval or ratio level measure.
Analytic Hierarchy Process (AHP) is a widely used method for prioritization, as well as decision making and forecasting. AHP utilizes pairwise relative comparisons and eigenvector calculations to calculate ratio scale priorities for the factors being considered. Pairwise comparisons have been found to be easier for respondents to make (e.g. how much do you prefer A more than B?), as well as being more accurate over absolute judgments (e.g. do you like A or B?). This eigenvector calculation is robust in that accurate ratio scale priorities can be obtained even from imprecise verbal judgments from respondents. However, the more imprecise the individual pairwise judgments, the more important is the use of redundant judgments, that is, more than the minimum required for a mathematical solution, in determining the sought after priorities.
When using AHP with a computer program such as the known program "Expert Choice," the user can make verbal, numerical or graphical pairwise comparisons. I have determined that graphical judgments tend to be more accurate than verbal judgments and thus require less redundancy. Additionally, I have determined that graphical judgments are easier for a respondent to justify than a precise numerical judgment (e.g. A is 2.73 times B).
Of the three pairwise modes available with computer displays, verbal, numerical and graphical, only graphical cannot easily be performed via a pencil and paper survey. Eliciting graphical ratio level responses having the highest level of accuracy and therefore requiring the least redundancy from respondents is not an easy task.
It is accordingly one object of the present invention to provide an apparatus that will enable users of surveys and questionnaires to elicit graphical ratio level responses from respondents.
Another object of the present invention is to provide an apparatus for determining the subjective relative ratio level of factors under consideration by a user.